Security systems used for the protection of secured areas are known. Such systems typically rely upon a fence or barrier around a secured area with one or more portals (e.g., doors, windows, etc.) that allow access by authorized persons into the secured area.
Each of the portals may have a sensor (e.g., a limit switch) connected to the door or window that detects opening of the door or window by an intruder. The sensors may be monitored by a local control panel. Upon activation of one of the sensors, the control panel may activate a local alarm that notifies persons within the secured area of the threat.
The control panel may include a user interface that controls arming and disarming of the security system. The user interface may be located on the control panel or near an entrance to the secured area.
In order to avoid false alarms, the control panel may have a built-in delay that begins after detection of opening of the door or window and before activation of the alarm. This delay may be used by an authorized person to disarm the security system through the user interface.
In more sophisticated security systems, an authorized user may use an access card in conjunction with a card reader to both open the door and deactivate the security system. However, access cards may be duplicated and card readers are subject to damage by criminals. Accordingly, better methods are needed to allow access into secured areas by authorized persons.